Hydraulic fittings and flanges

Date:10 Feb 2020

The basic element of almost every hydraulic system is a […]

The basic element of almost every hydraulic system is a series of fitting flanges for connecting pipes, tubes and hoses to pumps, valves, actuators and other components.

The flared fitting was developed years ago as a modification of the fitting and may still be the most commonly used design in hydraulic systems. Tightening the nuts of the assembly will pull the fitting into the flared end of the pipe, creating a reliable seal between the flared face and the fitting body. Since it is difficult to form a thick-walled pipe to generate a flare, it is not recommended to use it with a flare joint. The 37 degree flared joint is designed for thin-walled to medium-thick pipes in systems with operating pressures up to 3,000 psi. Suitable for hydraulic systems operating at temperatures from -65 ° to 400 ° F. It is more compact than most other fittings and can easily fit into metric tubing.

All metal accessories
The threads on the pipe fittings are tapered and depend on the stress generated by pressing the tapered threads of the male half of the fitting into the female half or component port. Pipe threads are susceptible to torque because they are torque sensitive, and overtightening can distort the threads excessively and create a leak path around the threads. In addition, when the vibration and temperature changes are large, the pipe thread is easy to loose, so the hydraulic system is no stranger.

1. Pipe fittings have given way to newer fitting designs to simplify assembly and maintenance and reduce or eliminate leaks. The display is 90 degrees. Adapter elbow with piping thread on one end, which is permanently fixed in the component port. The other end of the joint uses a straight pipe flare joint for pipe connection.
2. When using fittings in high-pressure hydraulic systems, leakage can occur around the threads. Because pipe threads are tapered, repeated assembly and disassembly will only distort the threads and exacerbate leaks, especially if forged fittings are used in cast iron ports. So thread sealant compounds, a potential contaminant, are recommended for pipe fittings, which is another reason most designers consider them obsolete in hydraulic systems.